A now defunct baseball website which, for a time, was the best place for intelligent baseball fans to gather and discuss the sport they love. An illegitimate offshoot of the fairly famous Baseball Prospectus website (and book), Primer was a forum designed to focus less on the SABR aspects of the Bill James fan generation and more on the baseball itself, with blogs dedicated to recent games and current news within the MLB establishment.
Though naturally inaccessible to the average Joe, BP2 had its own sector of popularity and, in time, became a port of call of sorts for not only fans, but knowledgeable (and fairly famous) baseball persons such as Rob Neyer, Aaron Gleeman and Peter Gammons.
Baseball Primer was a once in a lifetime experience which, now replaced by the pretentiously named Baseball Think Factory, will never be duplicated in the main stream market. There has not been and never will again be a forum which was as available and interesting to fans as it was to the objects of their fandom.